DE102009049445A1 - Micro valve for use as switch in e.g. medical application areas, has actuator embedded in carrier material, where carrier material exhibits radiation permeability on one side and actuator adopts stable condition by radiation - Google Patents

Abstract

The valve has an actuator made of a radiation dependent polymorphous material and embedded in a carrier material, where the carrier material exhibits radiation permeability on one side and the actuator adopts a stable condition by radiation. The radiation dependent polymorphous material consists of a thermo-sensitive material e.g. bi-metal, shape memory alloy and shape memory polymer. The polymorphous material comprises a hydrogel e.g. smart hydrogel, stimulus responsive hydrogel or acrylamide hydrogel and derivatives.

Description

The invention relates to a radiation-activated minimal mechanical microvalve or microswitch for fluidic microsystems. Powerless and potential-free actuation of the actuator by a radiation-permeable carrier material. The valve state or switch state can be detected via reflectance measurement without current and potential-free. As a radiation assimilator Bimetallschnappscheiben, shape memory materials or polymorphs are used.

State of the art

It is known that microvalves are realized by means of snap disks and their electrical heating ( DE 102 50 758 A1 05.13.2004). A status message is also requested electrically. The realization is very complicated.

It is also known that microvalves are manufactured in silicon technology. However, manufacturing requires high technological investment and is more expensive even in high volumes.

It is furthermore known that microvalves have been realized whose functional principle is based on materials having different coefficients of thermal expansion, which are connected to one another in a material-locking or positive-locking manner ( DE 201 16 898 U1 ). The mechanical bias of the actuator is not necessary here. However, cost-effective integration is difficult and electrical control necessary.

The invention is therefore based on the object to provide an improved microvalve that overcomes at least one of the above-mentioned disadvantages.

Detailed description of the invention

In a first aspect, the invention is directed to a microvalve or microswitch which, in contrast to the prior art, is cost-effective, electrically noncontacting with the fluid, easily integrated into a variety of substrates, and controllably employable without contact. This valve is intended to produce no significant heating of the surrounding materials by a pinpoint heating, and thus improve the switching times of such valves. In addition, the valve should enable a non-contact state determination so that security queries and controls (holding radiation) to allow. According to the invention, all aspects of the task are fulfilled by the features formulated in the claim.

• – mit der Verwendung eines Schnappscheibenelementes oder eines Formgedächtnismaterials oder eines Polymorphs, ohne elektrischer Kontaktierung, die Realisierung eines Ventils im Vergleich zu ähnlichen Konzepten deutlich günstiger ist.
• – der Aktor aus einem thermosensitiven Material besteht, welches sich, gemäß der Bezeichnung, mit einer induzierten Temperaturveränderung in eine geometrisch unterschiedliche Form wandelt
• – keine elektrischen Ableitungen zur Steuerung des Aktors im Trägermaterial notwendig sind, welches den Preis des Ventils deutlich vermindert.
• – keine elektrischen Ableitungen zur Zustandsbestimmung Aktors im Trägermaterial notwendig sind.
• – die Auswahl an Trägermaterialien und die Varianten der Aufbau- und Verbindungstechniken zunehmen.
• – kein Risikopotential durch eine elektrische Kontaktierung zu erwarten ist.
• – die Wärmeenergie direkt aufgenommen werden kann und nicht durch z. B. Heizelemente oder Widerstände übertragen werden muss.
• – die Erwärmung der Umgebungsmaterialien als auch des Fluids auf ein Minimum reduziert wird, da punktuell nur die Schnappscheibe erwärmt wird (bei optimaler Transparenz des Trägers oder bei direkter Schnappscheibenbestrahlung).
• – mit Integration des Ventils in ein Disposable, die Ansteuerung des Ventils kontaktlos über LED, Laser oder Induktion erfolgt und keine Verbindung (z. B. Kontaktstifte) zur Hardware besteht
• – Das Mikroventil kann, zur Verhinderung von physikalischen und chemischen Reaktionen, mit Chemikalien oder Gasen mit Gefahrenpotential in Kontakt kommen

The advantages with respect to the prior art are that

• - With the use of a snap disk element or a shape memory material or a polymorph, without electrical contacting, the realization of a valve compared to similar concepts is much cheaper.
• - The actuator consists of a thermosensitive material, which, according to the name, with an induced temperature change converts into a geometrically different shape
• - No electrical leads for controlling the actuator in the carrier material are necessary, which significantly reduces the price of the valve.
• - No electrical derivatives for determining the state Aktors in the carrier material are necessary.
• - the choice of support materials and the variants of the assembly and joining techniques increase.
• - No risk potential is to be expected by an electrical contact.
• - The heat energy can be absorbed directly and not by z. B. heating elements or resistors must be transmitted.
• - The heating of the surrounding materials as well as the fluid is reduced to a minimum, since selectively only the snap disc is heated (with optimal transparency of the wearer or with direct Schnappscheibenbestrahlung).
• - With integration of the valve into a disposable, the control of the valve is contactless via LED, laser or induction and there is no connection (eg pins) to the hardware
• - The microvalve may come into contact with hazardous chemicals or gases to prevent physical and chemical reactions

One embodiment of the invention is that the microvalve can be part of a fluidics provided with chemical or physical sensors.

The carrier material and its construction and connection technology must be selected only with regard to the fixation of the actuator and the radiation permeability out.

An embodiment of the invention will be described with reference to an outline ( 1 ). In this example, a bimetallic snap disk ( 1a ) in a structured film ( 3 ) introduced body of fluid. The fluid channel ( 2a ) is replaced by the snap-action disc ( 1a ) and the seal ( 4 ) permanently sealed. Through the transmission of radiant energy of the emitter ( 7 ) through the film on the snap-action disk, only the actuator is heated and snaps into position when the snap-in temperature is reached ( 1b ). This is the opening of the channel ( 2a ) and the fluid can move in the direction ( 2 B ) be transported. At the same time, at the moment convex curved disc, depending on the installation of the emitter ( 7 ) an increase of the reflected radiation by z. B. a photodiode ( 6 ).

LIST OF REFERENCE NUMBERS

1

Schnappscheibe

1b

Schnappscheibe ausgelenkt

2a

Fluidkanal Einlass

2b

Fluidkanal Auslass

3

Trägermaterial Folienschichten z. B. laminiert

4

Dichtung

5

Reflektierte Strahlung ausgelenkt

6

Photodiode

7

Emitter

8

Ventilhohlraum

Fig. 1

1

snap disk

1b

Deflected snap disc

2a

Fluid channel inlet

2 B

Fluid channel outlet

3

Carrier material film layers z. B. laminated

4

poetry

5

Deflected reflected radiation

6

photodiode

7

emitter

8th

valve cavity

Fig. 1 General structure

Description of the general structure

• – ein Trägermaterial,
• – einen Einlasskanal,
• – einen Auslasskanal,
• – eine Schnappscheibe, die in einer Kammer angeordnet ist, wobei die Kammer in einen oberen Abschnitt und einen unteren Abschnitt unterteilt ist und wobei der obere Abschnitt einen Zugang zu dem Einlasskanal und einen Zugang zu dem Auslasskanal aufweist,
• – eine Dichtung,

wobei die Schnappscheibe mit der Trägerfolie verbunden ist und durch Strahlungseinwirkung zwischen einer geschlossenen und einer geöffneten Position wechseln kann, wobei die Schnappscheibe in der geschlossenen Position an der Dichtung 4 anliegt und dabei jeweils einen Zugang zudem Einlasskanal und dem Auslasskanal verschließt und wobei die Schnappscheibe in der geöffneten Position den jeweiligen Zugang zu dem Einlasskanal und dem Auslasskanal freigibt und dadurch in der geöffneten Position eine fluide Kommunikation zwischen dem Einlasskanal und dem Auslasskanal ermöglicht.An emission-induced microvalve, wherein the microvalve comprises:

• A carrier material,
• An inlet channel,
• An outlet channel,
• A snap-action disc arranged in a chamber, the chamber being divided into an upper portion and a lower portion and the upper portion having access to the inlet channel and access to the outlet channel,
• - a seal,

wherein the snap-action disc is connected to the carrier foil and can change between a closed and an open position by the action of radiation, the snap-action disc in the closed position on the seal 4 thereby abutting one access each of the inlet channel and the outlet channel and wherein the snap disc in the open position releases the respective access to the inlet channel and the outlet channel and thereby allows in the open position fluid communication between the inlet channel and the outlet channel.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10250758 A1 [0002]
• DE 20116898 U1 [0004]

Claims (25)

A microvalve, wherein the microvalve comprises an actuator and a carrier material, wherein the actuator consists of a radiation-dependent polymorph and is embedded in the carrier material; wherein the substrate has radiation permeability at least one side and wherein the actuator assumes one of two stable states by radiation. The microvalve of claim 1, wherein the radiation emanates from a radiation source located inside or outside the substrate. The microvalve according to claim 1 or 2, wherein the actuator is movable or deformable embedded in the carrier material. The microvalve according to one of the preceding claims, wherein the radiation-dependent polymorph consists of a thermosensitive material. The microvalve of claim 4, wherein the thermosensitive material is selected from the group consisting of a bimetal, a shape memory alloy, a shape memory polymer, and a polymorph. The microvalve of claim 5, wherein the bimetal is selected from the group consisting of elements of 4 to 14 main group and 3 to 6 period of the periodic table and their alloys. The microvalve of claim 5, wherein the shape memory alloy is selected from the group consisting of NiTi (nickel titanium, nitinol) CuZn (copper-zinc) CuZnAl (copper-zinc-aluminum) CuAINi (copper-aluminum-nickel) FeNiAl ( iron-nickel-aluminum). The microvalve of claim 5, wherein the shape memory polymer is selected from the group consisting of disposable memory polymers, and optically crosslinkable and optically soluble polymers The microvalve of claim 5, wherein the polymorph is selected from the group consisting of hydrogel, smart hydrogel, stimuli-responsive hydrogel or acylamide hydrogel, and derivatives thereof. The microvalve of any one of the preceding claims, wherein the radiation source is selected from the group consisting of LED, laser radiation and induction radiation. The microvalve according to one of the preceding claims, wherein the microvalve has no electrical contacts. The microvalve according to one of the preceding claims, wherein the actuator is characterized by the specific energy-absorbing material, with simultaneous radiation transparency of the support material. The microvalve of any one of the preceding claims, wherein the actuator reduces the energy absorption of the surrounding materials by the direct specific energy intake. Use of the microvalve according to one of the preceding claims in current- or potential-critical application areas. The use of claim 14, wherein the current or potential critical applications include medical uses and / or explosive applications. The microvalve according to one of claims 1 to 14, wherein the reflection property of the actuator is selected so that the reflection of the radiation from the actuator determines its state via a radiation measurement. The state determination designated under 16 also makes possible without electrical contacting at the actuator and actuator environment The status message designated under 16 can also be carried out by a non-contact radiation measurement Use of the microvalve according to one of claims 1 to 14, wherein the microvalve is used as a switch. The microvalve according to one of claims 1 to 14, 17 or 19, wherein the radiation source can be used together with the actuator in a device unit or in a carrier material, wherein the distance of the components is limited only by the necessary energy transfer Use of the microvalve according to one of claims 1 to 14, 17 or 20, as a single or multiple constituent in a single-layer or multilayer fluidic card or in an injection-molding fluid. Use of the microvalve according to one of claims 1 to 14, 17 or 20, wherein the microvalve is reusable or is used for disposable use. The use of claim 21, wherein the microvalve is used in reusable fluidics or as a disposable. The microvalve according to one of the preceding claims, wherein the microvalve is part of a chemical and / or physical sensor system. The microvalve of any of the preceding claims, wherein the microvalve may be contacted with human body fluids.

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